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By M Vendrup, T C. Christensen, C Dube

The adsorptive and granulate forming MetClean™ process has been used at many locations in Northern Sweden, Norway, Denmark, France, Spain, Mongolia, Japan and Australia. It has been pilot tested and used in full scale treatment plants to remove metals from:mine watersleachate from solid waste in incineration flue gasleachate from fly ash damsleachate from landfill and waste ponds.The following paper provides details of pilot and plants tests on the effectiveness of MetClean™ in removing arsenic, antimony, barium, cadmium, copper, molybdenum, nickel, radium, uranium, vanadium and zinc. Results show that MetClean™ may reduce the concentration of these metals in treated effluent water to the one part per billion (ppb) range.The paper also finds that, for specific metals, the optimal adsorption condition depends on the:pH levelmolar relation between the specific targeted metal and the addition of iron (II) or manganese (II)type of oxidation agentssalinity levelpresence of other metals.The most effective pH level varies according to the targeted metal but falls within the pH 5 to pH 11 range. A compromise pH level may be set when more than one metal is targeted for removal at the same time and through only one process step. The removal efficiency of one or both metals may be affected by operating at a compromise rather than optimum pH level.The MetClean process generates non-hazardous solid waste. Waste can then be disposed of more easily than brine or sludge.CITATION:Christensen, T C, Vendrup, M and Dube, C, 2015. Pilot tests for heavy metals removal in mine water, in Proceedings MetPlant 2015, pp 404–415 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

About twelve months ago, owing to the increasing quantity of stone and dirt being drawn frQm the Victorian State Coal Mine due to the large amount of dead work below ground, cutting, faults, etc, and to the increasing quan#ty of banded coal beingworked, the writer was forced to consider the question of economy in handling the spoil at the surface. The method in operation at the time was to run out level dumps fro,m the, tipping floor of the heapstead, or brace, and to tip most of the skips of stone in tipplers at the ends of the dumps, the remainder of the skips being side-tipped to widen the dumps.The method, whilst quite satisfactory for dealing with a few skips of stone, was found to be costly as the dumps extended, and the number of skips to be dealt with increased from 300. to 400 per day of two shifts;. therefore, in order to expedite thework and cheapen its cost, the writer devised an improved method which may be qescribed as follows :-(1) The stone is tipped into a hopper car which holds about 10 skips(2) The hopper car is hauled up an inclined dump by means of an electric winch.(3) The spoil is dumped from the car forwards or to either side, as required.(4) The car is returned to the starting point for a further load.Plate I Fig. 1 gives an idea of the construction of the hopper car. In the illustration the car is in position for tipping to one side. The body of the car is supported on a ball race on the under carriage, and it can be swung round to tip in any required direction. The bottom of the hopper is extended to form a 4 ft. lip...

Jan 1, 1918

A field method combining solvent extraction and paper partition chromatography permits a simple and rapid semiquantitative estimation of gold in siliceous, argillaceous and sulphide ores. The method will facilitate the eyaluation of prospect samples in which the gold is too fine for separation by panning.Ethyl alcohol-hydrobromic acid mixtures are suitable for chromatographic development of the gold complex, and give clear reproducible definition of the gold zone. Substitution of commercial "methylated spirits" for the ethyl alcohol gives equally good definition, improving the potential of the method for field use.A batch of six samples in the range of 0·5 to 5·0 dwt/ton can be completed in two hours. The range may be extended by simple modification to higher or lower values.INTRODUCTIONIn a chromatographic method described previously (Lever 1958, Nevill and Lever 1959), gold from a standard volume of ore clamped between -plate glass was extracted by aqua regia on to the paper. After cautious drying the chromatogram was developed by an ethyl acetate-nitric acid-water mixture and gold was identified by spraying with stannous chloride solution. Sensitivity of the method in the low range was poor. The brown line obtained in the 1-3 dw/j ton range, caused by movement of gold in the reduced form, was not considered to be a satisfactory confirmation of the presence of gold. It was felt that the method would be improved by using a more elegant extraction and applying developing conditions which would produce a well defined purple line at all gold values. Iron was a limiting factor, and a method of eliminating its interference was needed.The method now developed overcomes these shortcomings, and gives a reliable result with a purple line for assay values of 0·5 dwtjton and over. Gold is dissolved from an...

Jan 1, 1964

Operations of the new copper smelter at Mount Isa commenced on the 6th February, 1953. Prior to this date a paper by R. V. Anderson (1953) outlined the smelter layout, proposed operation and expected performance.Nominally a 50-ton per day plant, output is currently at the rate of 85 long tons per day. In the first 3t years, of operation to 30th June, 1956, '71,339 tons of blister copper were produced. Operation has been stabilized' and a number of modifications to plant and operation have been made. This paper reviews the progress made to date.GENERAL LAYOUT AND EQUIPMENTThe general layout and equipment follows well-established practice as study of Figs. 1 to 4, and Appendix II will show. This diagrammatic representation of layout (Fig. 1) and flow sheet (Fig. 2) is intended for the purpose of brevity to take the place of a detailed plant description.Choice of site for the smelter was limited by the necessity for close proximity of the waste heat boilers to the powerhouse.Much excavation was necessary before foundation work commenced, but the plant is compact and further expansion is possible.CHARGE MAKE-UPRoaster charge initially comprised concentrates, purchased ores, revert materials, mine sulphide ore and barren sand. As purchased ore receipts increased and as domestic black rock oxidized ore became available, the latter two fluxes were eliminated from the charge. Fluxes at minus i-in. sizing are trucked from crushing plant or stockpile by motor lorries. Filtered mill concentrates are dropped from an overhead conveyor on to the storage patio floor adj acent to the two concentrate bins.

Jan 1, 1957

A large body of porphyry-type copper mineralization occurs at Panguna in southern BougainviIle. It is associated with the intrusion of quartz diorite/granodiorite into andesites, particularly with the contact zone. Metasomatism of both intrusives and andesite resulted in the formation of biotite pseudomorphing hornblende and the veining of the resultant biotite diorite and biotitized andesite by quartz-chalcopyrite veins with pink orthoclase and dark biotite selvages, respectively.The orientation of intrusives and veins appears to be controlled by premineralization fault-joint patterns in the intruded andesitic Kieta Volcanics.

Jan 1, 1968

A recent Evening Post Headline read 'Officialdoms Inertia Risking Millions in Growth Strategy'. The article beneath that headline outlined the difficulties encountered by the Government's growth strategy projects and included the paragraph 'public efforts by Government to brush up communication of the widespread nature of its growth strategy is believed to have been matched by efforts in private by some ministers to overcome their frustration at the constant delay while reports and paper work are moved between departments and through the system'. The article went on to point out that these delays could cost New Zealand millions of dollars in lost overseas exchange savings. We as responsible citizens should be appalled or at least concerned that such costly delays should or even could occur. But those on the outside of the system who spend much of their working life prodding, reminding, pleading, cajoling, even begging, the bureaucracy should be excused a smirk or a smile or even a good belly laugh. The Minister is usually a part of the bureaucracy passing judgment on someone else's proposals. This time the Government has plans of its own. Plans which it wishes to see implemented as rapidly as possible and even with the assistance of the precautionary National Development Act with its 'fast track' provisions those plans have got bogged down in the bureaucratic machine which this Government has done as much as any other to create. In the circumstances, the thought of Her Majesty's Ministers frustrated at the constant delay while reports and paper work are moved between departments and through the system is not unpleasing.

Jan 1, 1982

By P J. Mienie

The Palaeo-Proterozoic Transvaal Supergroup in the Northern Cape Province of South Africa is host to the largest known resources of high-grade hematite ore on the Southern African continent. These ores are currently being exploited at Sishen and Beeshoek. Hematite occurances on the Sishen South exploration project (some 65 km south of Sishen mine), are at present the focus of an intensive investigation. At both the Sishen and Sishen South deposits, mineralisation is found within lithologies belonging to the Transvaal and Oliphantshoek Supergroups. The Transvaal Supergroup comprises a basal, carbonate platform sequence (the Campbell Rand Subgroup) overlain by thick units of banded iron-formation belonging to the Asbestos Hills Subgroup. The Asbestos Hills Subgroup is unconformably overlain by sedimentary rocks of the Gamagara Subgroup. The latter Subgroup has been correlated with the lowermost unit of the Oliphantshoek Supergroup. The Sishen and Sishen South deposits are located close to the western margin of the Kaapvaal craton and have been subjected to intensive, structural deformation. Both localities have undergone folding, faulting and thrusting. Early regional tectonism (2400 - 1700 Ma) played a critical role in the genesis and preservation of the ores from younger erosive events. At both deposits, four similar iron ore occurrences have been recognised. The ores have developed in specific depositional environments and hence display unique physical, chemical and metallurgical properties:The bulk of the high-grade hematite comprises laminated and massive ores, which are found in the upper parts of the Asbestos Hills Subgroup. The laminated and massive ores are best developed in basinal and pseudo-graben structures. Collapse breccia ores of medium- and lower-grade are preserved within deep palaeosinkholes. The sinkholes have developed within the dolomites of the Campbellrand Subgroup. Lower-grade conglomeratic and gritty ores constitute the remainder of the deposits. These ores are found in the overlying clastic succession of conglomerates, shales and quartzites belonging to the Gamagara Subgroup. Although, there are many stratigraphic and lithological similarities between the Sishen and Sishen South deposits, there are also important differences, which will impact on the profitable exploitation of the ores. The most striking contrast between the deposits is their size and geometry. Sishen mine is a single pit operation with an opencast mineable reserve of 895 Mt. The Sishen orebody is thicker, more continous and significantly larger than the Sishen South deposit. The Sishen South deposit has a potential opencast reserve of 228 Mt. It comprises a number of small and narrow, isolated orebodies, spread over an area of ¦64 km2 . There is a significant difference in grade between the deposits. On average the orebodies of the Sishen South deposit have a higher iron content (+0.25 per cent Fe), less potassium (- 0.090 per cent K2O) and less phosphorus (-0.019 per cent P). The Sishen South deposit has less interbedded shale in the laminated and massive ores. The footwall of these high-grade ores is a light-density, intrusive sill, compared to banded iron-formation at Sishen. With a proposed heavy-medium separation plant at Sishen South, the impact of dilution on product grades is expected to be less than that currently experienced at Sishen.

Jan 1, 2002

Using Mineral Maps to Rank Potential Processing Behaviour

Sep 13, 2010

The paper outlines the history and current status of the VALMIN Code and sets out the background, methodology, results and recommendations of the Independent Review of the VALMIN Code undertaken during 2001 under the Chairmanship of Ian Goddard. The paper is based on the final report of the Taskforce, which was submitted to the Board of The AusIMM for consideration.

Jan 1, 2002

By Wilson D, Kirkland J

Compressed air energy storage (CAES) uses low cost off-peak energy to compress air and pump it into pressurised underground storage. Expanding the air through a modified form of gas turbine generates electrical energy when required. While generating power, a CAES station consumes approximately one-third of the gas required for the equivalent installed capacity of a conventional gas turbine. Air can be stored in underground rock caverns, caverns in salt domes, or in aquifers. Existing CAES power stations use caverns mined out of salt domes. Aquifer storage for CAES has been proposed, but not yet implemented. The groundwater in the aquifer would be displaced during air injection and when required the air would be extracted using the natural hydro-static pressure. Victoria has no salt domes, but has aquifers onshore in the Gippsland Basin with geological dome structures of suitable depth, discovery pressure, porosity, permeability and caprock for CAES development. Field tests costing several million dollars would be required to prove the suitability. The most suitable aquifer is near Seaspray, where several dome structures exist. The aquifer, comprising of coarse sands capped by coal and mudstone, is some 600 metres deep with a hydrostatic pressure of 6.3 MPa. Computer simulation of injection and extraction of air from the aquifer under various combinations of horizontal and vertical wells, permeability and tubing head pressures indicated the largest aquifer structure had the capacity to sustain a 300 MW station. A well field comprising of 24 directionally driven wells with a horizontal exposure to the aquifer would achieve the air flow rates required. Using plant similar to that recently installed at McIntosh Alabama USA, would mean high capital costs compared to standard gas turbine plant. However, a review of modem gas turbines indicated that they could be easily and economically adaptated to CAES duty. Adapting a 120 MW gas turbine would give 344 MW output. A separate air compression plant would be used. Economic evaluations indicate that, for gas prices above $1.95 per GJ, a 344 MW CAES plant is more economic for intermediate/reserve load duty than simple cycle gas turbines.

Jan 1, 1992

Lignite deposits of Central Otago Miocene Dunstan Formation accumulated on a broad alluvial plain and on deltas that flanked a large freshwater lake. The regional subsurface distribution and configuration of the lignite-bearing strata are identified within the context of depositional systems and placed into a genetically defined stratigraphic framework. The stratigraphic and depositional models constructed, should form an integral part of the geological assessment process to guide future regional or mine based lignite drilling programmes. Further testing and evaluation of the commercialy important lignite deposits in the Blackstone and Roxburgh Coalfields are required to adequately characterise the lignites and their geological setting, particularly to select methods of mining and wise uses of the lignite.

Jan 1, 1992

By H W. Wu, D Humphreys

The structure of a comprehensive research project into mine fires study applying the Ventgraph mine fire simulation software, preplanning of escape scenarios and general interaction with rescue responses is outlined. The project has Australian Coal Association Research Program (ACARP) funding and also relies on substantial mining company site support. This practical input from mine operators is essential and allows the approach to be introduced in the most creditable way. The effort is built around the introduction of fire simulation computer software to the Australian mining industry and the consequent modelling of fire scenarios in selected different mine layouts. Application of the simulation software package to the changing mine layouts requires experience to achieve realistic outcomes. Most Australian mines of size currently use a ventilation network simulation program. Under the project a small subroutine has been written to transfer the input data from the existing mine ventilation network simulation program to æVentgraphÆ. This has been tested successfully. To understand fire simulation behaviour on the mine ventilation system, it is necessary to understood the possible effects of mine fires on various mine ventilation systems correctly first. Case studies demonstrating the possible effects of fires on some typical Australian coal mine ventilation circuits have been examined. The situation in which there is some gas make at the face and effects with fire have also been developed to emphasise how unstable and dangerous situations may arise. The primary objective of the part of the study described in this paper is to use mine fire simulation software to gain better understanding of how spontaneous combustion initiated fires can interact with the complex ventilation behaviour underground during a substantial fire. It focuses on the simulation of spontaneous combustion sourced heatings that develop into open fires. Further, it examines ventilation behaviour effects of spontaneous combustion initiated pillar fires and examines the difficulties these can be present if a ventilation reversal occurs. It also briefly examines simulation of use of the inertisation to assist in mine recovery. Mine fires are recognised across the world as a major hazard issue. New approaches allowing improvement in understanding their consequences have been developed as an aid in handling this complex area.

Jan 1, 2005

For more than 15 years after the Northparkes orebodies were first discovered in 1976, the project was delayed by the need to find an economic way of mining the low-grade E26 deposit. The decision to use a low-cost block caving method to mine the orebody was made in the early-1990s; but the project's future did not solidify until 1993 when a radical new approach was adopted which sought to integrate business imperatives with technology and organisation strategies. The approach led to the establishment of a strategic vision which tied together all the components that could have a major impact on the project, to provide a framework for guiding strategic choices. The strategic vision strived to break away from the old rules of how mines are organised and operated; and involved finding imaginative new ways to radically redesign mining processes to achieve quantum leaps in performance.

Jan 1, 1997

A subsurface study of the Maria Lode and associated hydrothermal alteration of andesites within the Karangahake epithermal gold-silver deposit defined the local evolutionary sequence in the once active geothermal system.   Some implications for mining of epithermal deposits arise as a result.

Jan 1, 1984

By I Coombes, M Trim, Y Sun, M McRae, A Spiegl, H Lagger, A Amon, P Barraclough, M Villeneuve

The Brisbane Airport Link Project (AirportlinkM7) includes the design and construction of more than 12.5 km of tunnels, with the Kedron interchange including four ramp tunnels that intersect with mainline tunnels and result in caverns with spans of up to 26 m. These caverns are in highly variable ground conditions with less than 35 m of cover underlying residential neighbourhoods and commercial properties. The Kedron caverns were constructed using the sequential excavation method (SEM). Owing to complex geometry and excavation sequence, the caverns were designed based on numerical modelling methods, including both two- and three-dimensional models. These numerical methods were used to develop a suite of support types with excavation sequences for the expected range of ground conditions. A combination of methods that included in-tunnel monitoring (convergence monitoring and extensometers), probe holes, endoscope probes, face mapping and ground settlement measurements were used to verify performance of the tunnel support systems and to select and refine the appropriate support system for each section of the caverns. The construction monitoring data indicated that numerical modelling can provide a good basis for predicting the performance of large-span underground openings in highly variable ground conditions. This paper presents a comparison of the performance of the caverns predicted by state-of-the-art numerical models and the actual measured performance.CITATION:McRae, M, Villeneuve, M, Trim, M, Sun, Y, Barraclough, P, Spiegl, A, Amon, A, Lagger, H and Coombes, I, 2014. Brisbane Airport Link Project – design and construction of the 26 m span Kedron Caverns: comparing monitoring data with the design, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 295–306 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By J D. St George

Flyrock is the unexpected and undesirable projection of rock fragments during detonation of a blast and managing this risk is becoming an increasing challenge as urban development encroach toward mineral extraction sites. The basic factors associated with flyrock are discussed in relation to geology, blast design and management. Published data of historical flyrock events are investigated and compared with local information on incidents. Good agreement was found between the data sets. A computer program of flyrock was developed using projectile motion based on launch velocity and angle, rock size, shape and density. This deterministic model was coupled with a probability model to simulate blast events. The impulse time ?t of the explosive pressure was taken as the stochastic variable to replace launch velocity. The variables were calibrated to replicate field data. A simulation was executed to demonstrate the capability of the approach to defining flyrock danger zones. For a simplistic situation it was identified that an appropriate distance to be cordoned off for the blast danger zone is a radius of 120 m in front of the blast and 65 m behind.

Jan 1, 2001

The mining industry continues to be a major driver of the Australian economy generating over A$130 billion in export earnings in 2008/2009. However, the industry has been cited as a significant contributor to green house gas emissions. Australia's proposed carbon trading scheme, the Carbon Pollution Reduction Scheme (CPRS) will financially impact on mining operations; this calls for a holistic planning approach for mining operations taking into account the impact of the emissions trading scheme. Since carbon trading is a new area of study, particularly within Australia, the quantitative effect of the CPRS on the mining industry is uncertain and current mine planning practices do not directly consider emissions. This paper presents results of the study into the impact of the CPRS on a hypothetical large scale open pit operation, using a spreadsheet model based on linear programming and simulation. By varying the production rates, life of mine (LOM), carbon price and ore grades among other variables several scenarios were simulated to determine the impact of emissions trading scheme on the net present value of the project. This study found that the adoption of the proposed Carbon Pollution Reduction Scheme could impact mining operations in Australia by a three per cent to six per cent reduction in net present value, for carbon credit costs of $25/t to $50/t respectively. While the six per cent reduction in net present value for a mining operation is significant, rising fuel prices have had a similar effect in recent years. The most energy-intensive processes are the milling circuit and the flotation concentrator circuit. These processes are jointly responsible for up to 60 per cent of the total emissions, depending on the production rate and the level of offshore processing conducted. Clearly, the introduction of the CPRS makes it is imperative for mining companies to assess the impact of carbon emissions on a mining project during mine planning.

Dec 6, 2010

IN 1906, soon after his arrival in New Zealand, a brief article was prepared by the writer on "The Salient Features of the Economic Geology of New Zealand," for the Journal of Economic Geology. In November, 1907, a somewhat similar paper, entitled "The Mineral Wealth of New Zealand," was read at the Royal Colonial Institute in London. The present contribution to the Transactions...

Jan 1, 1909

By Edwards A. B

Occasional, sporadic and small occurrences of lollingite in the Broken Hill lode have been described,(l) mostly in the garnet sandstone in the foot-wall and under-wall of the Broken Hill lode. The lollingite contains appreciable percentages of cobalt and nickel and is regarded as an early mineral in the development of the lode; and, with the incoming of the sulphides, it has suffered considerable replacement by arsenopyrite. During the conversion of iron arsenide into the iron sulpho-arsenide, ilie nickel and most of the cobalt are removed in solution and are inferred to reappear in niccolite and other minerals that have been recorded among the later minerals of the Broken Hill lode. As a result of observations of the officers of ilie Broken Hill South Ltd., an occurrence of cobaltite can now be recorded which has developed by an analogous type of replacement.Cobaltite has previously been recorded from the Australian Broken Hill Consols lode in the vicinity of the rich deposits of silver, though not in contact with them. Cobaltite has been found in the northern extremity of the No. 2 lens of the Broken Hill lode at the 1,480 feet level of the Broken Hill South...

Jan 1, 1944

By S Lush, R Polglase

McConnell Dowell is pleased to be given the opportunity to present two papers to this conference. The first is a general discussion paper on our work in the field of slurry transportation. The second will be a technical paper on the development of a welded coupling compatible with urethane lined pipework. We trust that by discussing our recent work we can leave two lasting impressions on you: the versatility and useful role of slurry transportation, and the leading role taken by New Zealand in this technology This paper discusses three recent projects the New Zealand Steel Ironsand Transfer Line the Coarse Coal Ship Loading Technology the Nerang River Sand By-pass System. These have followed on from the other slurry projects with which McConnell Dowell has been associated such as the ironsand export trade at Waipipi and Taharoa. The New Zealand Contractors Federation awarded the Construction Award for 1986 to McConnell Dowell for the Ironsand Slurry Pipeline.

Jan 1, 1986